Pyrophoric mass.



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AUSTRIA-HUNGARY.

30 Drawing.

To all ehomitmegwncmu- Be 1t lmown that I, Dr. Cam. Fnnnrunn Anna VON Wnrseaon, chemist, a subject of the Era eror of Austria-Hungary, residing 5 at W e ener Hauptstrasse 57, Vienna, IV, Austr1a-Hungary,have invented certain new and useful Improvements in Pyrophoric Masses, of which th following is a specification.

This invention relates to improvements at pyrophoric masses that is to say of masses which when rubbed with a file or with a knife-blade give off sparks of great mtensitywhich may advantageously be used for gmtmg gases, liquids and solid bodies as well asfor the purposes of illumination, signaling and photography and has for its ob ect to manufacture these pyrophoric masses of such a composition that the same I are possessing great durability, hardness and resistance to decomposition by the influence of atmospheric air.

My new pyrophoric substance contains a 'metal of the cerium group, which group consists, as the term, group, is herein used,

of the rare earth metals, cerium and lanthanum; and I prefer to use, whenever prac tlcable, cerium. But as is well known by all skilled this art, it is nearly impossible commerciallyto manufacture pure cerium,

and commerclal cerium nearly always contalus in actual practice small parts of Such rare earth metals as neodime and praseodime. Hence, even where the principal rare earth metal used is cerium or a mixture consisting principally of cerium and lanthanum is used,

other rare earth metals may and will generally be found in the resulting pyrophoric alloy. But these other-rare earth metals 40 (e. g. neodirne and praseodime) are technicallay1 and economically of comparatively sm importance. Pure cerium when exposed to the air becomes coated with a thin layer of what appears to be suboxid but generally contains a small proportion of-nitrid, and this layer in contradistinction to the unattached metal has pyrophoric properties. Alloys of the meta s 01. the rare earths whichare rich in cerium behave like pure cerium. Now

it is a noteworthy fact that this layer is formed more quickly on the most powcrfully pyrophoric alloys consistin of rare earth metals and heavy metals, sucli as iron,

PYBOIKOBIC MASS.

Specification of lettersratent. Patented NOV.22, 1910. Application filed January 19, 1910. Serial No. 588,926.

alloys which are less pyrophoric. It ma be deduced from this fact that in probability the pyrophoric behavior of all alloys of the rare earth metals is essentially dependent on the speed with which the suboxid la er is formed. It may be taken as gener y true, therefore, that with the formation of suboxid layers the pyrophoric power of all rare earth metal alloys is increased. Since the substance constituting the said layer, which substance will in this specification be termed suboxid whatever its true nature may he, is tolerably stable in air, attempts to manufacture pyrophoric masses of rare earth alloys having suboxid admixtures in he mass, suggested themselves.

Now the invention has for its object a pyrophoric alloy containing a metal of the cerium group, above identified, this allo being thoroughly impregnated with sma. quantitie nitrids. ing such rare earth metal or an alloy of only rare earthmetals or of rare earth metals with other metals is first reduced to a fine powder or fine chips by abrasion or scra'pim', air being excluded if necessary. The pow er or chips are then compressed by strong filessure varying between 1000 and 25000 0S per square cm. in suitable molds. The compact mass thus obtained has a metallic appearance, but is not considerably more pyrophoric than the original substance. Pyrophority will considerably be increased The preferred procedure of makthe compressed mass, in a metal casing having thin walls and adapted to be closed; the heating is at first gentle and gradual, but rapid at the conclusion, finally attaining a temperature corresponding with incipient red-heat. A lively reaction ensues, the mass glows and frits together. i

The fritted mass exhibits a clear metallic luster on a freshly filed surface. The embedded suboxid is not visible to the naked eye. The mass is stable in air like the original alloy, but pomesses a higher degree of pyrophoric power than the original al loy, that to say, the partlcles sepa- 15 rated by means of any tool are more easily nickel, cobalt or manganese, than upon those pyrophoric masses is as follows: A

sequently heating the compressed mass s of suboxids or of suboxids and with a volume of air about equal to that of inflammable in the air and a. smaller me-'] chanical power sutlices to produce sheaves of case heating is roceeded withup to pyrophoric power of which is not appreciably greater than that possessed the original materia If the strongly pyrophoric alloyof cerium and'iron is subjected to'the foregoing treatment, a mass is obtained the yrophoric power of which is so increases that by lightly drawing a knife blade across it, an actual sheet of flame is produced. The masses containing suboxid sufi'er less loss in their pyruphoric power when made from 211- loys containing indifferent metals than when made from the pure alloys' Thus for certain purposes, such as for varying the hardness or increasing the durability or illuminating efiect, calcium, magnesium, alumini-. um, tin, zinc, lead or the like may be added up to 10 er cent. of the mass without particularly epreciating the pyrophoric power.

I desire in the following claims to be dis- -tinctly understood as including under the phrase, a metal of the cerium group, either cerium or lanthanum; and I have already explained hereinbefore that, in a commercial;- sense, it is practically impossible to obtain these two metals "free from a mixture with other rare earth metals. Hence, the latter will inevitably, from a commercial standpoint, enter the pyrophoric alloy but are of slight importance. Cerium and lanthanum, which constitute the cerium group in the terminology which I have herein adopted, are the rare earth metals susceptible of use in producing alloys having the pyrophoric properties hereinbefore alluded to and are, therefore, the only important ones to be considered.

1 What do claim as my invention and desire to secure by Letters Patent is: sparks, than with the original allo In I IL A pyrophoric alloy containing a metal sion, of the cerium group; said metal bein thorhomogeneous a loys may be obtained the its suboni v 2. A pyrophoric alloy containin a. metal of the cerium grou said metal bem thoroughly im regnated with small quantities of oughly impregnate with small quantities of its suboxid and its nitrid.

3. A pyrophoric alloy containing metals of the cerium group; said metals being thoroughly pregnated with small quantities of their suboxids.

LA pyrophoric alloy containing metals of the cerium group; said metals beingthoroughly impregnated with small quantities of their suboxids and their'nitrids.

5. A pyrophoric alloy containing cerium thoroughly impregnated with small quantities of its suboxi 6. A pyrophoric alloy containing cerium L- o In testimony whereof I afiix my signature in presence of two witnesses.

' CARL AUER VON WELSBACH.

Witnesses:

down L Hans Luz. 

